Biological Collection of Kidney Cells
Pseudoxanthoma ElasticumOur objective is to obtain human induced pluripotent stem cells from urine samples of PXE patients for further proteomic and metabolomic studies and treatment screening.
Phenotypic Expressions in a French Pseudoxanthoma-Elasticum Cohort
Pseudoxanthoma ElasticumThe cohort is intended to study the phenotypic expressions of the pseudoxanthoma elasticum (PXE) disease in various tissues (eye, skin, arteries, etc).
Natural History of GACI With or Without ARHR2 or PXE
Generalized Arterial Calcification in InfancyAutosomal Recessive Hypophosphatemic Rickets1 moreGeneralized arterial calcification of infancy (GACI) is an ultra-rare disorder with an estimated birth prevalence of around 1 in 400,000.1 GACI is generally fatal before birth or within the first six months after birth. The cause of death is frequently myocardial infarction or stroke. GACI is strongly associated with inactivating mutations in ectonucleotide pyrophosphate/ phosphodiesterase 1 (ENPP1). Many patients with GACI, including some without an ENPP1 mutation also present with mutations in adenosine triphosphate binding cassette transporter protein subfamily C member 6 (ABCC6). Autosomal recessive hypophosphatemic rickets type 2 (ARHR2) and pseudoxanthoma elasticum (PXE) are believed to be closely related to GACI. ARHR2 is caused by mutations in the ENPP1 gene and PXE is caused by mutations in the ABCC6 gene, with both being observed among patients with GACI. The natural history of GACI and in particular its long term morbidity and mortality are poorly understood. The primary objective of this study is to characterize overall survival among patients with GACI, over time from birth.
Arterial Wall Calcium Load in Pseudoxanthoma Elasticum
Pseudoxanthoma ElasticumType 2 Diabetes1 moreQuantification and preferential sites of arterial wall calcification within the coronary and lower legs arteries will be comared between Pseudo-Xanthoma elasticum(PXE) atients and type 2 diabetics and Chronic Kidney disease.
Characterization of Pseudoxanthoma Elasticum
Pseudoxanthoma ElasticumPseudoxanthoma elasticum (PXE) is a rare multisystem disorder of autosomal recessive inheritance (OMIM# 264800) and an estimated prevalence between 1:25.000 and 1:100.000. PXE is characterized by calcification and fragmentation of connective tissue rich in elastic fibers. Due to its high content of elastic fibers, Bruch Membrane in eyes of patients affected by PXE becomes thickened and calcified. The ocular phenotype is characterized by angioid streaks and peau d'orange but also choroidal neovascularizations and chorioretinal atrophy thereby in part mimicking the phenotype of age-related macular degeneration. The disease is due to mutations of the ABCC6-gene coding for a transmembrane protein which is mainly expressed in the liver and kidney. It is hypothesized that ABCC6 is involved in the excretion of a yet unknown factor from the liver which inhibits systemic calcification. In animal models several candidates for this factor have been identified but direct evidence for such a factor in patients with PXE is still missing. The primary purpose of this study is to further investigate the ocular phenotype of patients with PXE using multimodal imaging and functional testing to delineate the impact of Bruch membrane pathology on the eye. Furthermore, possible systemic anti-calcification factors, as well as associations with the vascular alterations are investigated to gain more insights into the pathogenesis of PXE..